FEBRUARY 18 - 22, 2008
TUESDAY, FEBRUARY 19
2:00 pm: Special Talk. "What the Most Metal-Poor Stars Tell Us About the Early Universe," Dr. Anna Frebel, McDonald Observatory, University of Texas at Austin. Phillips Auditorium.
Abstract: The chemical evolution of the Galaxy and the early Universe is a key topic in modern astrophysics. I am using the most metal-poor Galactic stars to reconstruct the onset of the chemical and dynamical formation processes of the Galaxy. These stars are an easily-accessible local equivalent of the high-redshift Universe. My discovery of two astrophysically very important metal-poor objects has recently lead to a major advance in the field. One object is the most iron-poor star yet found (with Fe/H=-5.4). The other stars displays the strongest known overabundances of heavy neutron-capture elements, such as uranium, and nucleo-chronometry yields a stellar age of 13.2 Gyr. Both stars already serve as benchmark objects for various theoretical studies with regard to nucleosynthesis processes in the early Universe. I will discuss how the abundances of metal-poor stars solidify and advance our understanding of the early Universe, and provide constraints on the nature of the first stars as well as their explosion mechanisms and corresponding supernova yields. One of my most recent studies thus employed a large samples of metal-poor stars to test theoretical predictions about the formation of the first low-mass stars. I will conclude with an outlook on how the combination of my near-field cosmology results with those of future facilities (MWA, JWST, GMT) will yield exceptional details about the formation of stars and Local Group galaxies.
WEDNESDAY, FEBRUARY 20
4:00 pm: Initiative in Innovative Computing (IIC) Seminar. "Interpreting Large Astronomical Datasets Using Large Grids of Models," Barbara Whitney, Astronomer, Space Science Institute. Preceded by refreshments at 3:45 pm. Room 330, 60 Oxford Street, Cambridge. Event parking is available at the 52 Oxford Street Garage [map]. Please inform the parking attendant you are attending the IIC seminar. (The IIC seminar series schedule is updated often with additional information and seminars.)
Abstract: Recent surveys in infrared astronomy have produced catalogs orders of magnitude larger than their predecessors. I discuss an approach to studying newly forming stars by producing a large theoretical dataset to compare to the catalogs. The physics as we know it is incorporated into radiative transfer models that output observable quantities. Going backwards from the set of models that fits the data for each source, we extract physical parameters of thousands of forming stars. I will present initial results, and lessons learned.
THURSDAY, FEBRUARY 21
11:00 am: Institute for Theory and Computation (ITC) Colloquium. "From Massive Cores to Massive Stars," Dr. Mark Krumholz, Princeton University. Pratt Conference Room.
Abstract: The similarity between the mass and spatial distributions of pre-stellar gas cores in star-forming clouds and young stars in clusters provides strong circumstantial evidence that these gas cores are the direct progenitors of individual stars. I describe a physical model for the evolution of massive cores into stars, starting with the initial phases of collapse and fragmentation, through disk formation and fragmentation, the later phases of stellar feedback, and finally interaction of the newly formed stars with their environments. This model shows that a direct mapping from cores to stars is the natural physical outcome of massive core evolution, and thereby allows us to explain many of the properties of young star clusters as direct imprints of their gas-phase progenitors.
12:30 pm: Optical and Infrared Astronomy Division Lunch Talk. "Piping Hot: Megacam Data Fresh From the Cluster," Ms. Maureen Conroy and Mr. John Roll, CfA. Pratt Conference Room.
Abstract: We will tour the new 'piper' cluster dedicated to megacam data reductions. We will showcase the features of the GUI navigation system for data, parameters and data products. And we will outline the current capabilities of the automated pipeline reductions.
4:00 pm: Colloquium. "Dusty Disks and Comets: Clues to the Formation and Evolution of the Solar System," Dr. Carey Lisse, Johns Hopkins University. (Anyone wishing to meet with the speaker should contact the host, Dr. Scott Wolk, ext. 6-7766.) Preceded by tea at 3:30 pm. Phillips Auditorium.
Abstract: With the Spitzer Space Telescope (SST) we are for the first time beginning to understand the details of how the composition and formation of our own Solar System compare to those of other stars in our Galaxy. This is a major question in astronomy, and recent, detailed observations by SST of comets (remnants of the solar systems proto-stellar nebula), proto-planetary disks around young stellar objects (YSOs), and debris disks around moderate-age stars have given us a collection of detailed spectra containing clues about our Galactic context. In this talk I will discuss these observations, which are comprised mainly of mid-infrared (5 to 40 micron) spectroscopy of dust grains and gas. Using the results from the recent Deep Impact and STARDUST space missions, we can now constrain the relative abundances of silicates, carbonates, water ice, amorphous carbon, sulfides, and polycyclic aromatic hydrocarbons (PAHs) in these environments. I will discuss the similarities and differences in the spectra, and their implications to larger questions of our Solar System's origins.
7:30 pm: Monthly Observatory Night for the Public. "Here Comes the Sun," Kelly Korreck, CfA. The lecture will be followed by telescopic observing, weather permitting. No tickets or reservations are necessary; however, seating is to the capacity of the hall. Doors open at 7:00 pm. Phillips Auditorium.
Abstract: Like a tantrum-prone child, our Sun goes through periodic outbursts. It is quiet now, but in a few years the Sun will boil with solar flares, generating violent space storms in the inner solar system. Astronomers are working to understand the Sun in hopes of eventually being able to predict solar flares with a space "weather forecast." Kelly Korreck will describe how their latest tool, the Hinode spacecraft, has provided new insights into solar activity.
FRIDAY, FEBRUARY 22
12:30 pm: Institute for Theory and Computation (ITC) Colloquium. Speaker: Stuart Wyithe, University of Melbourne. Topic: To be announced. Pratt Conference Room.
ITAMP WORKSHOP
ITAMP is cosponsoring a workshop in Okinawa, Japan, February 20 - 22, 2008, entitled "Cold Antimatter Plasmas and Application to Fundamental Physics." The workshop is being cosponsored with RIKEN, University of Tokyo, and the Society for Atomic Collision. The workshop organizers are: Y. Yamazaki (Univ. Tokyo & RIKEN), Y. Kanai (RIKEN), H. Sadeghpour (ITAMP, CfA). For more information visit our website.
SAO HUMAN RESOURCES NOTES
SAO Trust Fund Employees:
Please join us on Wednesday, February 27, from 2:00 to approximately 3:30 in Phillips Auditorium for a TIAA-CREF educational seminar on "Planning Ahead for Retirement." This seminar is targeted to individuals who are 10 or more years away from retirement. The presentation focuses on the three major questions that concern most participants in regard to their retirement:
In addition, the presentation will include information about the TIAA-CREF investments with emphasis on the lifestyle investment funds that have been recently added to our plan.
The seminar will be conducted by Sam Gagliardi, Senior Consultant, Individual Client Services, from the Boston office of TIAA-CREF. Mr. Gagliardi is a Certified Financial Planner with over 25 years of experience in the retirement and investment services industry.
Please contact Linda McDonald with questions concerning the TIAA-CREF Retirement Plan at (617) 496-7605, or via email to lmcdonald@cfa
Leave Donations Requested
Due to a medical emergency, Joyce Janjigian of the Solar, Stellar and Planetary Science Division has been approved as a leave donor recipient in the Leave Transfer Program. Any SAO Trust Fund employee who wishes to donate annual leave to Joyce should complete a Leave Donor Form and send it to MS 17.
Under the Leave Transfer Program, Trust Fund employees may only donate annual leave to other Trust Fund employees and Federal employees may donate annual leave only to other Federal employees. If you should have any questions or are not able to access the form, please contact Anne LeBlanc, ext. 5-7371.
Job Vacancies
An online listing of all current SAO job openings is available. For more information, please call Human Resources, ext. 5-7371, or view your nearest bulletin board.